To establish a method of producing a monoclonal antibody against human immunodeficiency virus (HIV) in wheat,two gene sequences coding the heavy chain and the light chain of the antibody were separately constructed in plant expression vectors containing an endosperm-specific promoter from oat and then co-introduced into wheat cultivar Yangmai 158 via particle bombardment.Polymerase chain reaction (PCR) analysis of transgenic wheat plants from T0 to T3 generations showed that the integration and inheritance of the two genes were stable.Reverse transcription-PCR analysis indicated that both genes were normally transcribed in wheat endosperm of transgenic plants.Enzyme-linked immunosorbent assays (ELISA) further confirmed that the antibody produced in transgenic wheat plants had specific antigen-binding capability.These results suggested that mammalian antibody can be stably expressed in wheat endosperm and wheat seeds may be used for the production of antibody with HIV-neutralizing activity.